Field of the Invention
The invention relates to an arrangement for current limitation which is suitable for integration into a power supply serving network and which has a superconductive conductor, which is attached to at least one plate like support composed of insulation material.
Description of Related Art
One such arrangement is known and is described in for example, BP 0 503 448 A2, DE 10 2004 048 646 B4 and DE 10 2006 029 722 B3. It serves to prevent short circuits in the power supply serving network. In addition, the properties of the superconductive materials will be utilized, which will be superconductive at sufficiently low temperatures and by exceeding a certain current strength, the critical current strength is transformed to the normal conductive state. The DC resistance of a superconductive conductor is zero by sufficient cooling, as long as the critical current strength is not exceeded. Suitable materials are, for example, oxide materials on the basis of rare earths (ReBCO) especially YBCO (yttrium-barium-copper-oxide) or BSCCO (bismuth-strontium-calcium-copper-oxide). Sufficiently low temperatures to bring such materials into the superconductive state lie, tor example, between 67K and 110K.
With the occurrence of a short circuit the critical current strength of a superconductive conductor is exceeded, whereby the transition from the superconductive state, with an accompanying negligible small electrical resistance of the material, into the normal conductive state, is accompanied with very high electrical resistance of the materials. Furthermore, in the normal conductive state the materials will heat up through its resistive losses and the electrical resistance increases. The transition of the materials from the superconductive into the normal conductive state takes place by exceeding the critical current strength very quickly, typically in the span of a few milliseconds. As a result, by the placement of one the known arrangements, quickly an electrical resistance in the network is switched on, which limits the short circuit, as a result the network and the arrangement itself are protected from a high current short circuit.
The known arrangement according to the previously mentioned document describes a superconductive conductor with bifilar construction arranged on sheath like supports. In dependence on the required conductor length, a suitable number of such supports are arranged in a housing acting as a cryostat. In the mounted position, for each phase of an alternating current such a cryostat would be used. The manufacture of the bifilar arranged superconductive conductor equipped with supports is costly. There, for each phase of the alternating current a correspondingly constructed cryostat would be used, whose space requirement for the construction is relatively large, especially then, when it concerns a three phase alternating current.